Description

The genus Sterna now contains a group of medium sized white terns that live in coastal waters.

The members of the genus Sterna are generally white, with black caps on the head. Most of them are plunge feeders, a dramatic site as they dive head-first in the sea. Most migrate, in some cases for massive distances. The Arctic Tern is the most impressive in that respect.

Like many genera there is currently much debate about the members of Sterna. Currently the RSPB and British Bird List place the Sandwich Tern in this genus as Sterna Sandvicensis, but other sources place it in the genus Thalasseus (crested terns).

The genus also used to contain the seven species currently in the genus Sternula (small white terns), but these are generally now considered to be a separate genus.

Classification
Order: Charadriiformes (Gulls, terns, plovers etc)
Family: Sternidae
Genus: Sterna

Number of Species: at least 13 (as of May 2015)

British Members of the Genus

Migrant Breeder
Sandwich Tern, Sterna Sandvicensis  
Common Tern, Sterna Hirundo
Roseate Tern, Sterna Dougallii 
Arctic Tern, Sterna Paradisaea